fix(bedrock): add inference profile prefixes and fix reasoning for additional models

- Add palmyra and pixtral to US cross-region inference profile prefix list
- Strip reasoning content from message history for non-reasoning models
- Exclude palmyra from reasoning variant generation to prevent unsupported params

Author: sfradkin

packages/opencode/src/provider/provider.ts

@@ -356,6 +356,8 @@ export namespace Provider {
                   "nova-2",
                   "claude",
                   "deepseek",
+                  "palmyra",
+                  "pixtral",
                 ].some((m) => modelID.includes(m))
                 const isGovCloud = region.startsWith("us-gov")
                 if (modelRequiresPrefix && !isGovCloud) {

packages/opencode/src/provider/transform.ts

@@ -51,6 +51,15 @@ export namespace ProviderTransform {
     model: Provider.Model,
     options: Record<string, unknown>,
   ): ModelMessage[] {
+    // Strip reasoning parts from assistant messages for models that don't support reasoning
+    if (!model.capabilities.reasoning) {
+      msgs = msgs.map((msg) => {
+        if (msg.role !== "assistant" || !Array.isArray(msg.content)) return msg
+        const filtered = msg.content.filter((part) => (part as any).type !== "reasoning")
+        return { ...msg, content: filtered }
+      })
+    }
+
     // Anthropic rejects messages with empty content - filter out empty string messages
     // and remove empty text/reasoning parts from array content
     if (model.api.npm === "@ai-sdk/anthropic" || model.api.npm === "@ai-sdk/amazon-bedrock") {
@@ -381,7 +390,8 @@ export namespace ProviderTransform {
       id.includes("kimi") ||
       id.includes("k2p5") ||
       id.includes("qwen") ||
-      id.includes("big-pickle")
+      id.includes("big-pickle") ||
+      id.includes("palmyra")
     )
       return {}